The Principle of Contingent Causation: The Impossibility of Infinite Regress.

[Angrboda]

@Angrboda

This is from the AMNH: "The Big Bang was the moment 13.8 billion years ago when the universe began as a tiny, dense, fireball that exploded. Most astronomers use the Big Bang theory to explain how the universe began. But what caused this explosion in the first place is still a mystery."

Does the AMNH have a quantum theory of gravity?   If not, then what they are saying isn't based upon science.  We do not have an adequate theory of physics to describe what happened at or before Planck time.  Period.  You can cherry-pick a popularizer of science like AMNH and wallow in ignorance if you like.  It just makes you look even less credible. You're just making Christians look like idiots. But I'll give you a chance. Please explain to us how the big bang theory leads to the conclusion that the universe began? If you can't do that, then you're simply repeating things that you like because they agree with what you believe. Show that you understand the physics well enough to explain why it leads to the conclusion that the universe began? If you can't do that, then you have a problem, because I can explain why it does not lead to that conclusion. Stop mindlessly repeating shit and show us you're more than a copy-pasta bot.

Extrapolation of the expansion of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past. This irregular behavior, known as the gravitational singularity, indicates that general relativity is not an adequate description of the laws of physics in this regime. Models based on general relativity alone cannot fully extrapolate toward the singularity.

This primordial singularity is itself sometimes called "the Big Bang", but the term can also refer to a more generic early hot, dense phase[22][notes 2] of the universe. In either case, "the Big Bang" as an event is also colloquially referred to as the "birth" of our universe since it represents the point in history where the universe can be verified to have entered into a regime where the laws of physics as we understand them (specifically general relativity and the Standard Model of particle physics) work. Based on measurements of the expansion using Type Ia supernovae and measurements of temperature fluctuations in the cosmic microwave background, the time that has passed since that event—known as the "age of the universe"—is 13.8 billion years.

Despite being extremely dense at this time—far denser than is usually required to form a black hole—the universe did not re-collapse into a singularity.

Wikipedia || Big bang
[emphasis mine]